A wide variety of accessories such as letter trays, calendar and memo holders, pencil holders, vertical files and the like have long been available for office use. Throughout the years, the basic function of such office accessories has remained constant. Typically, they are intended for use either on a desk top or other horizontal surface, or on a wall or other vertical surface, and only in a horizontal or vertical position of orientation.
A relatively recent development in office furnishings is the open-plan office concept utilizing modular wall panel assemblies to define invididual work areas or stations within an otherwise open area. The popularity of this concept has resulted in a number of companies entering the marketplace and producing such wall panels. These manufacturers market wall panels having channels at each end for mounting cabinets, shelves, horizontal work surfaces, display panels and other wall hung units. Accessory units designed for mounting on a particular wall panel of one manufacturer normally cannot be mounted on another manufacturer's panel. So far as we are aware, office type accessories intended for use on both horizontal and vertical work surfaces in both conventional and open-plan environments were not available prior to our invention.